1. Field of the Invention
The invention relates to a system for orthopedic or neurological surgery on a patient, and more particularly to a retractor system for anterior cervical spine surgery.
2. Description of the Related Art
Anterior cervical fusion is one of the most commonly performed spine procedures in the world. One of the nuances in anterior cervical spine surgery is adequate retraction. There have been no recent advances in anterior cervical retraction.
One commonly used anterior cervical retractor system is part of the TrimLine® anterior cervical discectomy & fusion instrument set available from Medtronic Sofamor Danek. Another commonly used anterior cervical retractor system is the Shadow-Line® anterior cervical fusion retractor and distraction system available from Cardinal Health V. Mueller® Neuro/Spine Products. The TrimLine® and Shadow-Line® anterior cervical retractor systems do provide ease of use, multiple blade lengths, and a good self-retaining mechanism. However, the TrimLine® and Shadow-Line® anterior cervical retractor systems can still have shortcomings including displacement of the retractor, tissue creep into the operative field, and the need to reposition the retractors in multilevel cases. In particular, one of the difficulties with the TrimLine® and Shadow-Line® anterior cervical retractor systems is that there is more resistance on the blade retracting the trachea and esophagus medially as compared to the blade retracting the carotid artery laterally. This results in the retractor wanting to become displaced out of the wound when retracting on the blades.
Another of the nuances in anterior cervical spine surgery is placement of the anterior cervical plate. Traditional methods of plate placement involve the surgeon holding the plate with a device in one hand and then fixating the plate with a screw driver in the other hand. This can result in the plate sliding or becoming angled as the surgeon switches instruments with his/her hand during screw placement. Plate placement can be particularly important with extendable plate systems.
For example, Globus Medical sells a plate called the XTEND® anterior cervical plate that is a system that not only addresses a patients' immediate needs but also considers long-term treatment. The XTEND® anterior cervical plate provides surgeons with the ability to later treat adjacent levels as needed. An extender plate may be added to any primary plate with no disruption to the primary construct. The XTEND® primary plate preserves intact adjacent levels and accepts an extender plate if adjacent levels need stabilization. When treating an adjacent level with an extender plate, the primary plate and screws remain in place, preserving primary bone purchase and an extender plate can be placed adjacent to any primary plate without disrupting the primary plate or screws, eliminating the need to remove the primary construct. Plate placement is particularly important with the primary plate as a primary plate placed crooked can impede the ability to place an extender plate onto the primary plate in the future.
What is needed therefore is an anterior cervical retractor system that would address these shortcomings and would make it significantly easier for a surgeon to apply the anterior cervical plate to the vertebra.